1. Field of the Invention
The present invention is concerned with an image recording member which is capable of recording an image thereon by merely supplying energy such as external heat, electric current, light rays, and so on without the need for particular chemicals which is free from periodical maintenance and which is suitable for use in the dry-reproduction process. More particularly, the invention relates to an image recording member which is applicable to various recording materials for receiving signals such as those from a facsimile, outputs from computers and their terminal equipment, data of various kinds from measuring instruments for industrial, medical, business, and various other purposes, and various photographic materials and reproduction materials.
2. Description of Prior Art
With the development of the so-called information oriented society in recent years, various image recording apparatuses and recording materials therefor, which have so far been used mainly in the professional fields, have now gained their popularity in general offices and even in the for business as well as private uses. In this consequence, various stringent requirements have come to be imposed on these reproduction apparatuses and the recording materials therefore mostly from the standpoint of convenient and easy handlings. Particularly desirable is a recording material which is capable of recording an image thereon from energy sources such as light rays, electric current, external heat, and so forth without the need for chemicals, and which is free from periodical maintenance and suitable for use in the dry reproduction process.
Such a recording material has been disclosed in various patents. There has previously been disclosed, for example, a dry silver as taught in U.S. Pat. No. 3,457,075, etc.; photosensitive recording material having therein free radical photographic elements as the principal constituent, or the so-called electrical discharge recording material, in which a surface layer is perforated by a recording needle, or a stylus which electrically produces heat to remove the surface layer and to expose a coloured layer underneath such surface layer as disclosed in Japanese Patent Publication Nos. 37-13032, 37-13033, and 37-13034, electrically sensitive recording material in which an image is formed by reducing a metallic compound dispersed in an electrically insulative resin to a free metal by means of electric conduction as proposed in Japanese Patent Publication Nos. 38-22341, and 44-29630; and, a heat-sensitive recording material as taught in Japanese Patent Publication No. 45-14039;.
These recording materials, however, have not yet attained satisfactory performances in respect of color tone, contrast, and other qualities of the recorded image as well as shelf life, image stability on the recording material, and hygienic safety of the raw materials against pollution, and so on.